Device for transmitting fluctuations in the voltage or current of an alternating-current system to electroresponsive or magnetically-operated devices.



G. J. VAN SWAAY & H. l.- KEU'S.

DEVICE FOR TRANSMITTING FLUCTUATIONS IN THE VOLTAGE 0R CURRENT OF AN ALTERNATING CURRENT SYSTEM TO ELECTROHESPONSIVE 0R MAGNETICALLY OPERATED DEVICES.

APPLICATION FILED JAN.23. ms.

1,275,631 v Patented Aug. 13, 1918;

2 SHEETS-SHEET l- Van waay H.I Kaub.

Arrorey.

I e. 1. VAN SWAAY 1 H. I. KEUS.

DEVICE FOR TRANSMITTING FLUCTUATIONS IN THE VOLTAGE 0R CURRENT OF AN ALTERNATING CURRENT SYSTEM TO ELECTRORESPONSIVE 0R MAGNETICALLY OPERATED DEVICES. APPLICATION FILED JAN. 2a, 1915.

1 ,27 5,63 1 Patented Aug 13, 1918.

2 SHEETSSHEET 2.

InV nI'w Van fiwaa G H. I. Klzyg jng . UNITED STATES PATENT OFFICE.

GERARDUS JAGOBUS VAN SWAAY OF DELFT, AND HENRI ISAAC KEUS, 01' HEN GELO,

NETHERLANDS.

nnvrcn FOR TRANSMITTING OPERATED DEVICES.

FLUCTUATIONS 1N THE VOLTAGE 03 CURRENT OF AN ALTERNATING GUBIBEN T SYSTEM TO ELECTROBESPONSIVE OR MAGNETIOALLY- Application flled January as, 1915. Serial No.

To all whom it ma 3 concern.-

Be it known that we, Professor GERARDUS JAcoBUs VAN SWAAY, at Delft, Netherlands, and HENRI IsAio KnUs, electrical engineer, residing at Hengelo, Netherlands, formerly of Delft, Netherlands, subjects of the Queen of the Netherlands, have invented certain new and useful Devices for Transmitting Fluctuations in the Voltage or Current of an Alternating Current System to Electroresponsive or Magnetically-Operated Devices, of which the following is a specification.

This invention relates to means with the aid of'which fluctuations in the voltage or current in an alternating current system cause fluctuations in the operation of apparatus responding to the firsttmentioned fluctuations.

The object of the invention is to provide such means in which any fluctuations in the voltage or current of an alternating current system cause considerably stronger fluctuations in the to the first mentioned fluctuations. With this means it is for instance possible to make electro-responsive magnetically operated, and other devices, adapted to be influenced or controlled by fluctuations in the voltage or current in an alternating current system, respond effectively to small fluctuations in said voltage or current to which such devices would otherwise not respond. The means according to the invention consists mainly of a transformer. of well known construction, comprising a core having a plurality of legs with different magnetic resistances so arranged and connected that a magnetic flux induced in part of said legs can divide and pass through the remaining legs with different magnetic-resistances, part of which first mentioned legs are provided with primary windings so proportioned and connected that under normal conditions part of said remaining legs are saturated with lines of force and the other part of said renaining legs are unsaturated. The primary windings of this transformer are, in accordmce with the condition whether the means :hall act on voltage or current fluctuations, :onnected either across-or in the mains of he system; Fluctuations'in the voltage or urrent respectively of the primary wind- Speciflcation of Letters Patent.

civil engineer, residing operation of apparatus respond-,

Patented Aug e, 1918. 3,869.

ings will have hardlyany effect on the mag a netic flux in the saturated circuit but will produce strong fluctuations in the magnetic flux in the normally unsaturated legs. This 'well known property is employed for real- 1z1ng the object of the invention in a very simple and effective manner by arrangin on the unsaturated legs of the core secon ary wlndings and by connecting said secondary windings to the electro-responsive devices or by providing the attenuated legs-of the core with a1r gaps and by arranging the magnetically operated devices so that they are underthe influence of the attenuated leg in the air gas circuit. heinventiton is reference to the acompanying drawings in which the transformer for the sake of clearness is illustrated with three legs and in .every instance provided with an air gap in the attenuated circuit. It should be understood, however, that the higher magnetic resistance in the unsaturated leg may be ob tained by other means and that the core may comprise any suitable number oflegs of which any suitable part may be'so proportioned 'as to be normally saturated, while the remaining legs are unsaturated.

Figure 1 shows diagrammaticall' the transformer in combination with an e ectroresponsive device. y

Fig. 2 is a modification of the arrangement according to Fig. 1. t Fig. 3 shows diagrammatically an arrangement in which the transformer is used in combination with an electro-responsive device for regulating or controlling the voltage of an alternating current'generator.

further described with 1g. 4 represents the transformer in comcomprises a y v leg 5, so that for instance if windings 4 arranged nected across the mains tenuated. lln the example shown in the provided in this leg 7. To obtain the required efiect this air gap will generally be longer than the air gap in the ordinary transformers, comprising a core of a similar construction. The primary windings 4 are so proportioned that under normal conditions the magnetic flux induced by the current traversing them saturates the the core is built up of soft iron laminations, the number of lines of "force directed through this leg amounts to over 10,000 per squarecentimeter. Fluctuations in the magnetic flux in the leg 3 will have hardly any sheet on the flux in the leg 5. On the other hand such fluctuations will produce disproportionally increased fluctuations in the leg 7. Any fluctuation in the ampere turns of the primary windings 4 therefore results in considerably stronger fluctuations inthe magnetic induction in the unsaturated leg '2', and if on this leg secondary windings are arranged the potential at th drawings an air gap 6 is terminals of these windings will also be subject to considerable fluctuations. We have found that fluctuations of say 10% in the number of ampere turns of the primary windings may be magnified to fluctuations of 100% in thepotential induced in such secondary windings. It is obviously immaterial whether thefiuctuations in the number of ampere turns in the primary windings originate from variations in the number of.turns or from fluctuations in the current. The latter may be due to variations in the voltage in an alternating electric circuit, when the primary windings are connected across the conductors as shown in the drawings. The transformer may also be used for responding to fluctuations in the current in the conductors of the circuit by connecting theprimary windings in one of the conductors.

In the embodiment according to Fig. 1 this transformer is used in comblnation with "secondary windings and an electro-responsive device. The secondary windings 8 arranged on the air gap leg, as and for the purpose described above, are connected to a coil 7 11 provided with a movable soft iron core 10. This core carries a mercury cup 9 inv fluctuations in the force 10 is drawn into the coil 11 cause a reciprocatin movement of There y contacts 12 reaching into this cup will alternately get out of contact with the mercury and be such a manner that with which the core on this leg con' A great number of other devices may use ar est plungedinto thesame so that the windings 13 are in part or wholly short circuited.

The electro-responsive device is only shown diagraatically' and by way of example. be without departing. from the spirit of the invention. I. Fi .Zfor instance shows an embodiment 1n w ich the electro-responsive device for short circuiting the windings consists of a 0011 11 with movable core 10, which latter is attached to a balancing lever 14. One end of this lever is electrical y connected to one of the terminals of windings 16 to be short clrcuited, while the other terminal of said wmdlngs isconnected to a contact 15. Oscillations set up in the lever 14 cause a periodic closing and opening of the circuit of the coil 16L The lever may make a large number of oscillations.

A very useful embodiment of the invention is illustrated in Fig. 3. The arrangement shown is a combination of the transformer described above with a short circuiting relay of much the same construction as the relay according to Fig. 2 and in which the circuit to be closed and opened contains the field regulator of the exciter of an alternating current generator. The arrangement is especially suited for controlling the voltage in an alternator. The primary windings 3 of the transformer are connected across two conductors leading from the alternator 23. The alternator illustrated in. this figure is a three phase alternator; the invention ma however, as well be applied to a single or two phase alternator. Instead of a coil 16 as in Fig. 2 the balancing lever and the contact control the field regulator 19 by periodically short circuiting same. The balancing lever is very sensitive as in the well known Tirrill regulator. It now for some reason the voltage between the conductors, to which the primary windings 3 are connected drops the magnetic flux in the unsaturated leg 7 will be weakened considerably with the result that the windings 11 release the core 10 whereupon the contact 15 is closed by the lever 14 and the field resistance of the exciter is short circuited. The voltage of the alternator will increase with the rise in voltage of the eXciter resulting from this short circuit. If the alternator voltage has attained the required value again the core 10 "is drawn into the coil 11 thus causing the opening of the contact 15 by the lever 14 and switching the field regulator of the exciter into the circuit of its field windings. As stated above the lever 14 may be so constructed andbalanced that it may make a large number of oscillations per second. As will be clearly understood, however, the high degree of exactness at which the voltage of the alternatorcan be regulated or kept constant with this arrangement vention is connected. The prlmary wind- 3 of the core 2 are con-' ings 4 on the leg I nected between the mains 1. The secondary windings 18 are arranged on the saturated leg 5. Variations in the ampere turns of the relatively smaller fluctuationsin the potential induced in the-secondary windings 18.

In order to make the secondary circuit, how- 'ever, independent of any fluctuations in the voltage on the rimary side we arrange on the unsaturated windings 8, and the windings 18 so that the electromotive force of the windings 8 reduce the electromotive force of the windings .18; In this mannerthe small fluctuations in the electromotive force of the windings 18 may be controlled to any extent; they may even be neutralized entirely as is clear from the following example. Assumed' the primary voltage be 110 volts proportioned that under normal conditions a voltage of say 140 volts will be induced in same. Assuming further that the voltage induced in the windings 8 amounts to 30 volts the resulting voltage between the mains 19 will be 110 volts. If new the primary voltage drops say 10% the voltage induced in the windings 18 will decrease to say 130 volts. If the windings 8 are suitably chosen the voltage of these windings will, however, fall to 20 volts so that the resulting voltage between the mains 19 is still 110 volts. Instead of keepin the voltage constant the windings 8 may e so proportioned that the voltage is regulated to a required extent. The combination shown in this embodiment is particularly suited to supply current to the voltage coils of alter natmg watt-hour meters, which are being calibrated.

The combination according to Fig. 4 is also well adapted for large currents. In such case the arrangement may be used for primary windings will therefore causeleg 7 of the transformer connect them in series with and the windings 18 so 4 Intestimony whereof we afilx photometrical purposes or for feeding the ighting mains in factories in which the mains is not constant.

voltage on the according to this inven- The combinations tion for operating relays have the advantage that small fluctuations in the voltage or current in the primary circuit will produce strong actions of the relays so that the latter will be made comparatively more sensitive and will positively act upon small primary fluctuations. By these means no-l'oad relays and minimum switches may be constructed to out out at fluctuations in the primary circuit of 10 to 20 er cent.

Having now escribed our invention, what weclaim as new ters Patent is and desire to secure by Letv In an electric current system, an alternat- I ing current generator, a direct current exciting generator adapted to supply the magnet eld coils of said alternating current generator with direct current, a transformer comprising a core having three legs of different magnetic resistances so arranged and connected that a ma etic flux induced in one of said legs can dlvide and passthrough the remaining legs withdifferent ma netic resistances, a primary winding on' sai .first mentioned leg so proportioned and connected that under normal conditions one of said remainin legs is saturated with lines of forcean the other of said remaining le s is unsaturated, conductors connecting sald primary winding to the mains of said alternating current generator, a secondary winding arranged on said unsaturated leg only for producing a secondary electromotive force, fluctuating disproportionately with fluctuations in the voltage impressed u on said primary winding, conductors lea ing from said secondary winding, an electro-re- 'sponsive device connected to said conductors, contacts adapted to be opened and closed 1n .ra id succession by said electro-responsive evice, conductors leading from said contacts, and a field resistance of said excitsaid conductors and in the field windings generator. vour signatures in presence of two witnesses.

GERARDUS JAGOBUS VAN HENRI ISAKG KEUS. Witnesses:

AI. JURRIANS, A. C. Nansen.

swan. 

